This invention relates to a combined hydraulic-mechanical drive for wheeled vehicles. The invention utilizes a novel valve system that senses when a wheel loses traction. It then diverts hydraulic power to other wheels. The invention eliminates the need for a differential.
Prior art devices exist that combine hydraulic and mechanical drive to a vehicle axle, however, these devices have been primarily directed to tracked vehicles. Wheeled vehicles having mechanical all wheel drive utilize a differential for each axle. These differentials are heavy and costly. The space requirements necessary to maintain sufficient ground clearance increase the vehicle's center of gravity. An axle having a differential requires a large space between the drive wheels to acommodate the differential housing. The vehicle's floor pan must be either raised above the differential, or a raised tunnel around the axle must protrude in the vehicle's floor. Differential's are not as efficient in transferring power to the wheels in all wheel drives.